Sonic boom
An aircraft going supersonic produces a sharp double crack that arrives with no warning.
How to tell
- A distinct double bang, close together
- Extremely sharp onset, no build-up
- Felt over a very wide area at nearly the same moment
- No smoke, no fire response, nothing to see afterwards
When it usually happens
Daytime, no seasonal pattern.
Heard one just now?
Report it and we will tell you what it most likely was. More reports from different directions make it far easier to pin down.
Report what you heard